create three .aspx files
treeviewdataset.aspx
treeviewdataset.aspx
autopostback=true
treenodesrc=categories.aspx
runat=server/>
categories.aspx
mycon=new sqlconnection(server=localhost;uid=sa;pwd=secret;database=northwind)
strquery=select categoryname as text,'products.aspx?catid='
+ltrim(str(categoryid)) & _
as treenodesrc from categories as treenode for xml auto, xmldata
cmdcategories=new sqlcommand(strquery,mycon)
dscategories=new dataset
dscategories.readxml(cmdcategories.executexmlreader(),xmlreadmode.fragment)
dscategories.datasetname=treenodes
dscategories.writexml(response.outputstream)
end sub
products.aspx
mycon=new sqlconnection(server=localhost;uid=sa;pwd=secret;database=northwind)
strquery=select productname as text from products as treenode & _
where categoryid=@categoryid for xml auto, xmldata
cmdproducts=new sqlcommand(strquery,mycon)
cmdproducts.parameters.add(new sqlparameter(@categoryid,request.querystring(catid)))
mycon.open()
dsproducts=new dataset
dsproducts.readxml(cmdproducts.executexmlreader(),xmlreadmode.fragment)
dsproducts.datasetname=treenodes
dsproducts.writexml(response.outputstream)
mycon.close()
end sub